The U.S. Pat. Nos. 5,970,768, 5,983,690 and 5,987,953 of James Thomas Killop and Robert E. Roseliep disclose a machine for roll forming power transmission formations, i.e., splines, in a round workpiece. With such machines, a pair of slide assemblies conventionally mount a pair of toothed forming racks of elongated shapes for movement in opposite directions as each other from an end-to-end relationship to an overlapping relationship to engage a round workpiece therebetween and provide roll forming of the splines. With such spline rolling, the spacing of the forming racks is critical to provide accurate formation of the shape of the splines. This has conventionally been done by the use of tapered wedges that require a setup operation of the associated machine. Since the size of the workpiece can vary from one heat treat batch to the next, it is also necessary at times to provide a different setup operation during a single run of the same part upon movement from one batch to the next.